As a related art, for example, Patent Literature 1 discloses the technology that moves an image portion, such as a pointer for navigation or a main window image for radio, displayed on a display screen in association with a manipulation on a remote touchpad portion positioned distantly from the display screen. The user interface apparatus disclosed in Patent Literature 1 includes a remote touchpad portion and a control portion. The remote touchpad portion detects a manipulator's manipulation using his or her finger, for example. The control portion associates the finger movement detected by the remote touchpad portion with movement of a map and a pointer.
In addition, the control portion acquires a distance from the remote touchpad portion to the finger. Suppose a case where the acquired distance to the finger is less than a predetermined height such as three centimeters (cm), for example. In such a case, the control portion associates the finger manipulation detected by the remote touchpad portion with the manipulation to move the pointer on the display screen. In contrast, suppose a case where the distance to the finger acquired by the control portion satisfies a predetermined range of heights between 5 and 7 cm. In such a case, the control portion associates the finger manipulation detected by the remote touchpad portion with the manipulation to change the main window image for radio to a manipulation wait window image for radio.
According to the above-mentioned configuration, a manipulator can adjust the height of his or her finger with reference to the remote touchpad portion, select an intended image portion from the image portions such as the pointer for navigation and the main window image for radio, and manipulate the selected image portion.